High CPU when IIS running

[penfold]

I've got a bit of a strange one here. I am seeing high CPU usage - lsass.exe if I start a website on IIS. From my troubleshooting it keeps pointing towards a problem with AD but this machine does not have this role. It is used for AV services which run on a website. If I stop the website CPU is normal. If I start it CPU usage jumps through the roof. From what I can see there have been no changes/updates. Currently this server is a test server and not fully in production but Id like to know what the sudden jump in CPU.

 

Only resolution I saw with someone who had similar problem was to create a new server and do a fresh install. Not something I want to do. Anyone seen anything similar with IIS?